The originating IP address is more significant, but that belongs to
OrgName: ACRONOC INC
OrgID: ACRON-1
Address: 1415 Louisiana St
Address: Suite 12Y Box 8
City: Houston
StateProv: TX
PostalCode: 77002
Country: US
and is also not suspicious.
Not suspicious ?
Oh what it is to be young and innocent when it comes to matters internet.
Step 1: Google ACRONOC INC
Result : "Houston Texas Colocation, Dedicated Servers, VPS Solutions ..."
Step 2: Conclude that one of their customers is deliberatley or unknowingly running an open relay.
Step 3: Send spam message with full headers to abuse at acronoc.com
And finally.... the whole thing stinks of alarm bells suspicious if you just look at the URLs it's trying to take you to. I don't see skype dot com anywhere.